Neuroleptic malignant syndrome quetiapine

A 19-year-old schizophrenic patient taking risperidone 6 mg/day and olanzapine 20 mg/day had a creatine kinase activity of 6940 U/l without clinical manifestations of neuroleptic malignant syndrome when he switched to clozapine (dose not stated) the creatine kinase fell to about 300 U/l. Because he developed granulocytopenia, he was given quetiapine instead, and the creatine kinase again rose to 3942 U/l but fell after 4 days to 389 U/l without withdrawal of quetiapine. 

Although quetiapine seems to cause a lower incidence of extrapyramidal symptoms, a case of neuroleptic malignant syndrome has been described (9). 

Concomitant administration of quetiapine and fluvoxamine reportedly caused neuroleptic malignant syndrome (18). 

Matsumoto R, Kitabayashi Y, Nakatomi Y, Tsuchida H, Fukui K. Neuroleptic malignant syndrome induced by quetiapine and fluvoxamine. Am J Psychiatry 2005 162 812. 

An increase in the serum levels of carbamazepine or its epoxide metabolite has been reported in patients given loxapine, haloperi-dol, quetiapine, risperidone, or chlorpromazine with amoxapine. Toxicity has occurred. Thioridazine appears not to raise car-bamazepine-10,11-epoxide levels. Isolated cases of Stevens John-son syndrome have occurred In patients taking antipsychotics with carbamazepine. Carbamazepine may reduce levels of many of the antipsychotics. A case of neuroleptic malignant syndrome had been described in a patient taking antipsychotics and carbamazepine. See also Antipsychotics + Antiepileptics , p.707. 

Cases cf Neurotoxicity Toxicity at therapeutic or subtherapeutic levels was reported in three cases. In two of these cases, the role of lithium is questionable. In one case of a rapidly fatal presentation of neuroleptic malignant syndrome (NMS) in a 72-year-old woman whose lithium level was 1.5 mM, the authors report a lithium-induced fatal NMS because she was not prescribed an antipsychotic [84 ]. However, her presentation is also consistent with fatal catatonia, sepsis, or unknown consumption of an antipsychotic, none of which were ruled out, and all of which are more likely than lithium-induced NMS. A second case in which a delirium with dyspraxia, but not ataxia in a 57-year-old man with a lithium level of 0.44 mM, that resolved after discontinuation of botii lithium and tricyclic antidepressant medication, was felt to be an interaction between the lithium and the antidepressant [85 ]. Lithium may have played a role, but he had been on lithium for years, and had developed anticholinergic problems with quetiapine previously, suggesting that the anticholinei c effects of the tricyclic antidepressant were more important in the delirium than the lithium. The third case of a 65-year-old man with multisystem atrophy becoming considerably worse with lithium at a level of 1.1 mM, is much more likely to represent lithium-related neurotoxicity at therapeutic levels [86 ]. 

A case of neuroleptic malignant syndrome is reported in a 36-year-old male receiving methadone, venlafaxine and quetiapine IR (50 mg daily) with history of hepatitis C and hypothyroidism [215 ]. Another case of neuroleptic malignant syndrome in a 48-year-old female occurring 1 montix after initiating quetiapine XR is reported [216 ]. 

Akyuz F, Oflaz S, Ustun C, Karlidag GE, Demirel I. Neuroleptic malignant syndrome during the use of extended release quetiapine a case report. BCP 2012 22(4) 352-4. 

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